I've got some 3 year old Nokian WR G2 SUV tires that are primarily used from November to April as snow tires. I noticed that there is some mild cracking between the tread blocks, and I just wanted to see what people thought. The date stamp on all four tires is "0511". I'm honestly not too worried about it, but I'm not an expert either. I emailed Nokian out of boredom a couple hours ago, so I'm curious to see what they say as well.